High-Purity CaF2 Crystals & Optics Calcium Fluoride Windows & Lenses
Unlock peak optical performance with our high-purity Calcium Fluoride (CaF2) crystals, windows, and lenses. Engineered for demanding optics, our CaF2 components deliver exceptional broadband transmission from Vacuum Ultraviolet (130nm) to Mid-Infrared (10 microns).Featuring high thermal stability, ultra-low fluorescence, and a high laser damage threshold, these precision optical components are ideal for excimer lasers, Raman spectroscopy, thermal imaging, and semiconductor lithography. Whether you need VUV-grade substrates or custom AR-coated lenses for industrial or research applications, we deliver unmatched optical clarity and precision.
Technical Specifications
| Parameter | Value |
|---|---|
| Product | CaF2 — Calcium Fluoride Single Crystal, Cubic Fluorite Structure, Optically Isotropic |
| Transmission Range | 0.13–10 µm (VUV through LWIR) — >90% T 190-2500nm; VUV-grade for 193nm lithography |
| Refractive Index | 1.51 @0.19µm; 1.434 @0.59µm; 1.40 @5µm — very low, low dispersion; zero dn/dT at 1.7µm |
| Abbe Number | ~95 — extremely low chromatic dispersion; the standard for apochromatic optics |
| Hardness / Solubility | Knoop 158.3 (3× harder than BaF2) | 0.0017g/100g H2O (100× less soluble than BaF2) |
| Density / Melting Pt | 3.18 g/cm³ | ~1,360-1,418°C |
| dn/dT / Thermal Cond. | −10.6 × 10⁻⁶/°C | 9.71 W/m·K |
| Grades Available | VUV-grade (193nm excimer, ultra-low impurity) | IR-grade (FTIR, thermal imaging, lower cost) |
| Primary Applications | 193nm DUV lithography lenses, FTIR spectroscopy, excimer laser windows, apochromatic microscope objectives, high-energy laser optics |
Product Overview
CaF2 (Calcium Fluoride) is the premier deep-UV to mid-IR optical crystal — the only material combining 0.13-10µm transparency, n~1.43 (lowest among IR crystals), Abbe ~95 (extraordinary apochromatic color correction), Knoop 158 hardness (3× BaF2), and 100× lower water solubility than BaF2. These properties make CaF2 irreplaceable for: 193nm DUV lithography lenses (the optics that manufacture every advanced semiconductor chip), FTIR beamsplitters, excimer laser windows, and apochromatic microscope objectives. Princeton Powder supplies VUV-grade and IR-grade CaF2 — optical blanks, polished windows, lenses, prisms, and epi-ready substrates.
Technical Specifications
| Parameter | Specification |
|---|---|
| Crystal Structure | Cubic, Fm3m (fluorite), optically isotropic, cleaves on (111) |
| Transmission | 0.13–10 µm (VUV-grade); >90% T 190-2500nm |
| Refractive Index | 1.51 @0.19µm; 1.434 @0.589µm; 1.40 @5µm |
| dn/dT / Abbe | −10.6×10⁻⁶/°C; zero dn/dT at 1.7µm | Abbe ~95 |
| Density / Melting | 3.18 g/cm³ | ~1,360-1,418°C |
| Knoop Hardness / Solubility | 158.3 (3× BaF2) | 0.0017g/100g H2O (100× lower than BaF2) — non-hygroscopic |
| Thermal Cond. / Expansion | 9.71 W/m·K | ~18.9×10⁻⁶/K |
| Grades | VUV-grade (193nm, ultra-low impurity) | IR-grade (0.2-10µm, lower cost) |
| Surface Quality | λ/10 flatness; 10-5 to 60-40 S/D; IBS AR coatings available; max ~300mm diameter |
Why Choose Princeton Powder CaF2
- The Only Material for 193nm Lithography: At 193nm, fused silica solarizes and compacts under billions of pulses. CaF2's superior UV damage resistance makes it the irreplaceable lens material — the optics that print every advanced CPU and GPU.
- Abbe 95 — Apochromatic Without Exotic Glasses: Extraordinarily low dispersion + low index enables apochromatic doublets focusing UV-VIS-IR to the same point — critical for broadband spectroscopy and multi-wavelength laser systems.
- 100× Less Water-Soluble Than BaF2: Polished surfaces stable for years under normal atmospheric conditions — no protective coating required.
- VUV & IR Grades — Right Material, Right Price: VUV-grade for lithography/excimer lasers. IR-grade for FTIR/thermal imaging — lower cost, same CaF2 quality.
Applications
193nm DUV Lithography Lenses
CaF2 is the irreplaceable lens material for ArF immersion scanners — the optics manufacturing every advanced semiconductor at 7nm, 5nm, 3nm nodes.
FTIR Spectroscopy Beamsplitters
Broad 0.13-10µm transmission, low index, chemical stability — the standard beamsplitter substrate for FTIR spectrometers and gas analyzers.
Excimer & High-Power Laser Windows
High bulk damage threshold at 193/248/308nm — standard window/output coupler for excimer lasers used in semiconductor annealing, LASIK, and industrial processing.
Frequently Asked Questions About Calcium Fluoride CaF2 Crystals, Windows
CaF2 vs BaF2 — which fluoride?
CaF2: 3× harder, 100× less soluble, Abbe 95 apochromatic, only choice for 193nm lithography. BaF2: ~1µm further IR (12µm), more radiation-hard, scintillation (0.6ns). Princeton Powder supplies both.
VUV-grade vs IR-grade?
VUV: ultra-low impurity (transition metals <10ppb, OH <1ppm), optimized for 193nm. ~2-5× more expensive. IR: standard purity for 0.2-10µm — FTIR, thermal imaging, lower cost.
Is CaF2 sensitive to thermal shock?
Less susceptible than BaF2 due to higher strength, but avoid >10°C/min changes — especially for large-aperture optics where thermal gradients cause figure distortion.